Comparative Study between Ivabradine Versus Bisoprolol Effects for Heart Rate Control on Hemodynamics and Clinical Outcomes in Patients with Septic Shock

Background: Septic shock is associated with excessive sympathetic outflow, high plasma catecholamine levels, myocardial depression, vascular hypo-reactivity, and autonomic dysfunction. Typically, patients have a low resistance, high cardiac output circulation with tachycardia and arterial hypotension that may be poorly or even nonresponsive to exogenous catecholamine vasopressors. The aim of the present study was to compare the effect of ivabradine vs bisoprolol for heart rate control on the hemodynamics and clinical outcomes in patients with septic shock.

Methods: The study was carried out on 90 patients, aging from 18 to 60 years of both sex presented with septic shock in ICU. Patients were randomly classified into 3 equal groups each of 30 patients. Group I (Control group) received conventional therapy. Group II (Bisoprolol group) received conventional therapy plus bisoprolol 5 mg once daily & one placebo pill on 12 hrs interval via nasogastric tube for 7 days. Group III (Ivabradine group) received conventional therapy plus ivabradine 5 mg twice daily on 12 hrs interval via nasogastric tube for 7 days.

Results: Both bisoprolol and ivabradine effectively lowered heart rate in septic shock patients but ivabradine was more effective than bisoprolol. Both bisoprolol and ivabradine did not affect mean blood pressure, with ivabradine being more effective in maintaining blood pressure than bisoprolol. Noradrenaline dose was lower in ivabradine group in comparison with the other two groups. As regard to stroke volume & cardiac output, there was improvement in ivabradine group in comparison with bisoprolol and control groups. As regard to serum lactate level, there was improvement in ivabradine group in comparison with the other two groups. Both bisoprolol & ivabradine resulted in reduction in LOS & 28-day mortality with no significant difference between both groups.

Conclusions: Controlling heart rate in septic shock patients with either bisoprolol or ivabradine improves outcomes. Ivabradine is better than bisoprolol in maintaining hemodynamics and improving tissue perfusion parameters.